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x86: Optimize {str|wcs}rchr-sse2 

The new code unrolls the main loop slightly without adding too much
overhead and minimizes the comparisons for the search CHAR.

Geometric Mean of all benchmarks New / Old: 0.741
See email for all results.

Full xcheck passes on x86_64 with and without multiarch enabled.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
This commit is contained in:
Noah Goldstein 2022-04-21 20:52:28 -05:00
parent c2ff9555a1
commit 5307aa9c18
4 changed files with 348 additions and 453 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
sysdeps/x86_64/multiarch/strrchr-sse2.S
View File

@ -17,7 +17,7 @@
<https://www.gnu.org/licenses/>. */
#if IS_IN (libc)
# define strrchr __strrchr_sse2
# define STRRCHR __strrchr_sse2
# undef weak_alias
# define weak_alias(strrchr, rindex)

3
sysdeps/x86_64/multiarch/wcsrchr-sse2.S
View File

@ -17,7 +17,6 @@
<https://www.gnu.org/licenses/>. */
#if IS_IN (libc)
# define wcsrchr __wcsrchr_sse2
# define STRRCHR __wcsrchr_sse2
#endif
#include "../wcsrchr.S"

528
sysdeps/x86_64/strrchr.S
View File

@ -19,210 +19,360 @@
#include <sysdep.h>
#ifndef STRRCHR
# define STRRCHR strrchr
#endif
#ifdef USE_AS_WCSRCHR
# define PCMPEQ pcmpeqd
# define CHAR_SIZE 4
# define PMINU pminud
#else
# define PCMPEQ pcmpeqb
# define CHAR_SIZE 1
# define PMINU pminub
#endif
#define PAGE_SIZE 4096
#define VEC_SIZE 16
.text
ENTRY (strrchr)
movd %esi, %xmm1
ENTRY(STRRCHR)
movd %esi, %xmm0
movq %rdi, %rax
andl $4095, %eax
punpcklbw %xmm1, %xmm1
cmpq $4032, %rax
punpcklwd %xmm1, %xmm1
pshufd $0, %xmm1, %xmm1
andl $(PAGE_SIZE - 1), %eax
#ifndef USE_AS_WCSRCHR
punpcklbw %xmm0, %xmm0
punpcklwd %xmm0, %xmm0
#endif
pshufd $0, %xmm0, %xmm0
cmpl $(PAGE_SIZE - VEC_SIZE), %eax
ja L(cross_page)
movdqu (%rdi), %xmm0
L(cross_page_continue):
movups (%rdi), %xmm1
pxor %xmm2, %xmm2
movdqa %xmm0, %xmm3
pcmpeqb %xmm1, %xmm0
pcmpeqb %xmm2, %xmm3
pmovmskb %xmm0, %ecx
pmovmskb %xmm3, %edx
testq %rdx, %rdx
je L(next_48_bytes)
leaq -1(%rdx), %rax
xorq %rdx, %rax
andq %rcx, %rax
je L(exit)
bsrq %rax, %rax
PCMPEQ %xmm1, %xmm2
pmovmskb %xmm2, %ecx
testl %ecx, %ecx
jz L(aligned_more)
PCMPEQ %xmm0, %xmm1
pmovmskb %xmm1, %eax
leal -1(%rcx), %edx
xorl %edx, %ecx
andl %ecx, %eax
jz L(ret0)
bsrl %eax, %eax
addq %rdi, %rax
/* We are off by 3 for wcsrchr if search CHAR is non-zero. If
search CHAR is zero we are correct. Either way `andq
-CHAR_SIZE, %rax` gets the correct result. */
#ifdef USE_AS_WCSRCHR
andq $-CHAR_SIZE, %rax
#endif
L(ret0):
ret
/* Returns for first vec x1/x2 have hard coded backward search
path for earlier matches. */
.p2align 4
L(next_48_bytes):
movdqu 16(%rdi), %xmm4
movdqa %xmm4, %xmm5
movdqu 32(%rdi), %xmm3
pcmpeqb %xmm1, %xmm4
pcmpeqb %xmm2, %xmm5
movdqu 48(%rdi), %xmm0
pmovmskb %xmm5, %edx
movdqa %xmm3, %xmm5
pcmpeqb %xmm1, %xmm3
pcmpeqb %xmm2, %xmm5
pcmpeqb %xmm0, %xmm2
salq $16, %rdx
pmovmskb %xmm3, %r8d
pmovmskb %xmm5, %eax
pmovmskb %xmm2, %esi
salq $32, %r8
salq $32, %rax
pcmpeqb %xmm1, %xmm0
orq %rdx, %rax
movq %rsi, %rdx
pmovmskb %xmm4, %esi
salq $48, %rdx
salq $16, %rsi
orq %r8, %rsi
orq %rcx, %rsi
pmovmskb %xmm0, %ecx
salq $48, %rcx
orq %rcx, %rsi
orq %rdx, %rax
je L(loop_header2)
leaq -1(%rax), %rcx
xorq %rax, %rcx
andq %rcx, %rsi
je L(exit)
bsrq %rsi, %rsi
leaq (%rdi,%rsi), %rax
ret
.p2align 4
L(loop_header2):
testq %rsi, %rsi
movq %rdi, %rcx
je L(no_c_found)
L(loop_header):
addq $64, %rdi
pxor %xmm7, %xmm7
andq $-64, %rdi
jmp L(loop_entry)
.p2align 4
L(loop64):
testq %rdx, %rdx
cmovne %rdx, %rsi
cmovne %rdi, %rcx
addq $64, %rdi
L(loop_entry):
movdqa 32(%rdi), %xmm3
pxor %xmm6, %xmm6
movdqa 48(%rdi), %xmm2
movdqa %xmm3, %xmm0
movdqa 16(%rdi), %xmm4
pminub %xmm2, %xmm0
movdqa (%rdi), %xmm5
pminub %xmm4, %xmm0
pminub %xmm5, %xmm0
pcmpeqb %xmm7, %xmm0
pmovmskb %xmm0, %eax
movdqa %xmm5, %xmm0
pcmpeqb %xmm1, %xmm0
pmovmskb %xmm0, %r9d
movdqa %xmm4, %xmm0
pcmpeqb %xmm1, %xmm0
pmovmskb %xmm0, %edx
movdqa %xmm3, %xmm0
pcmpeqb %xmm1, %xmm0
salq $16, %rdx
pmovmskb %xmm0, %r10d
movdqa %xmm2, %xmm0
pcmpeqb %xmm1, %xmm0
salq $32, %r10
orq %r10, %rdx
pmovmskb %xmm0, %r8d
orq %r9, %rdx
salq $48, %r8
orq %r8, %rdx
L(first_vec_x0_test):
PCMPEQ %xmm0, %xmm1
pmovmskb %xmm1, %eax
testl %eax, %eax
je L(loop64)
pcmpeqb %xmm6, %xmm4
pcmpeqb %xmm6, %xmm3
pcmpeqb %xmm6, %xmm5
pmovmskb %xmm4, %eax
pmovmskb %xmm3, %r10d
pcmpeqb %xmm6, %xmm2
pmovmskb %xmm5, %r9d
salq $32, %r10
salq $16, %rax
pmovmskb %xmm2, %r8d
orq %r10, %rax
orq %r9, %rax
salq $48, %r8
orq %r8, %rax
leaq -1(%rax), %r8
xorq %rax, %r8
andq %r8, %rdx
cmovne %rdi, %rcx
cmovne %rdx, %rsi
bsrq %rsi, %rsi
leaq (%rcx,%rsi), %rax
jz L(ret0)
bsrl %eax, %eax
addq %r8, %rax
#ifdef USE_AS_WCSRCHR
andq $-CHAR_SIZE, %rax
#endif
ret
.p2align 4
L(no_c_found):
movl $1, %esi
xorl %ecx, %ecx
jmp L(loop_header)
.p2align 4
L(exit):
xorl %eax, %eax
L(first_vec_x1):
PCMPEQ %xmm0, %xmm2
pmovmskb %xmm2, %eax
leal -1(%rcx), %edx
xorl %edx, %ecx
andl %ecx, %eax
jz L(first_vec_x0_test)
bsrl %eax, %eax
leaq (VEC_SIZE)(%rdi, %rax), %rax
#ifdef USE_AS_WCSRCHR
andq $-CHAR_SIZE, %rax
#endif
ret
.p2align 4
L(cross_page):
movq %rdi, %rax
pxor %xmm0, %xmm0
andq $-64, %rax
movdqu (%rax), %xmm5
movdqa %xmm5, %xmm6
movdqu 16(%rax), %xmm4
pcmpeqb %xmm1, %xmm5
pcmpeqb %xmm0, %xmm6
movdqu 32(%rax), %xmm3
pmovmskb %xmm6, %esi
movdqa %xmm4, %xmm6
movdqu 48(%rax), %xmm2
pcmpeqb %xmm1, %xmm4
pcmpeqb %xmm0, %xmm6
pmovmskb %xmm6, %edx
movdqa %xmm3, %xmm6
pcmpeqb %xmm1, %xmm3
pcmpeqb %xmm0, %xmm6
pcmpeqb %xmm2, %xmm0
salq $16, %rdx
pmovmskb %xmm3, %r9d
pmovmskb %xmm6, %r8d
pmovmskb %xmm0, %ecx
salq $32, %r9
salq $32, %r8
pcmpeqb %xmm1, %xmm2
orq %r8, %rdx
salq $48, %rcx
pmovmskb %xmm5, %r8d
orq %rsi, %rdx
pmovmskb %xmm4, %esi
orq %rcx, %rdx
pmovmskb %xmm2, %ecx
salq $16, %rsi
salq $48, %rcx
orq %r9, %rsi
orq %r8, %rsi
orq %rcx, %rsi
movl %edi, %ecx
subl %eax, %ecx
shrq %cl, %rdx
shrq %cl, %rsi
testq %rdx, %rdx
je L(loop_header2)
leaq -1(%rdx), %rax
xorq %rdx, %rax
andq %rax, %rsi
je L(exit)
bsrq %rsi, %rax
L(first_vec_x1_test):
PCMPEQ %xmm0, %xmm2
pmovmskb %xmm2, %eax
testl %eax, %eax
jz L(first_vec_x0_test)
bsrl %eax, %eax
leaq (VEC_SIZE)(%rdi, %rax), %rax
#ifdef USE_AS_WCSRCHR
andq $-CHAR_SIZE, %rax
#endif
ret
.p2align 4
L(first_vec_x2):
PCMPEQ %xmm0, %xmm3
pmovmskb %xmm3, %eax
leal -1(%rcx), %edx
xorl %edx, %ecx
andl %ecx, %eax
jz L(first_vec_x1_test)
bsrl %eax, %eax
leaq (VEC_SIZE * 2)(%rdi, %rax), %rax
#ifdef USE_AS_WCSRCHR
andq $-CHAR_SIZE, %rax
#endif
ret
.p2align 4
L(aligned_more):
/* Save original pointer if match was in VEC 0. */
movq %rdi, %r8
andq $-VEC_SIZE, %rdi
movaps VEC_SIZE(%rdi), %xmm2
pxor %xmm3, %xmm3
PCMPEQ %xmm2, %xmm3
pmovmskb %xmm3, %ecx
testl %ecx, %ecx
jnz L(first_vec_x1)
movaps (VEC_SIZE * 2)(%rdi), %xmm3
pxor %xmm4, %xmm4
PCMPEQ %xmm3, %xmm4
pmovmskb %xmm4, %ecx
testl %ecx, %ecx
jnz L(first_vec_x2)
addq $VEC_SIZE, %rdi
/* Save pointer again before realigning. */
movq %rdi, %rsi
andq $-(VEC_SIZE * 2), %rdi
.p2align 4
L(first_loop):
/* Do 2x VEC at a time. */
movaps (VEC_SIZE * 2)(%rdi), %xmm4
movaps (VEC_SIZE * 3)(%rdi), %xmm5
/* Since SSE2 no pminud so wcsrchr needs seperate logic for
detecting zero. Note if this is found to be a bottleneck it
may be worth adding an SSE4.1 wcsrchr implementation. */
#ifdef USE_AS_WCSRCHR
movaps %xmm5, %xmm6
pxor %xmm8, %xmm8
PCMPEQ %xmm8, %xmm5
PCMPEQ %xmm4, %xmm8
por %xmm5, %xmm8
#else
movaps %xmm5, %xmm6
PMINU %xmm4, %xmm5
#endif
movaps %xmm4, %xmm9
PCMPEQ %xmm0, %xmm4
PCMPEQ %xmm0, %xmm6
movaps %xmm6, %xmm7
por %xmm4, %xmm6
#ifndef USE_AS_WCSRCHR
pxor %xmm8, %xmm8
PCMPEQ %xmm5, %xmm8
#endif
pmovmskb %xmm8, %ecx
pmovmskb %xmm6, %eax
addq $(VEC_SIZE * 2), %rdi
/* Use `addl` 1) so we can undo it with `subl` and 2) it can
macro-fuse with `jz`. */
addl %ecx, %eax
jz L(first_loop)
/* Check if there is zero match. */
testl %ecx, %ecx
jz L(second_loop_match)
/* Check if there was a match in last iteration. */
subl %ecx, %eax
jnz L(new_match)
L(first_loop_old_match):
PCMPEQ %xmm0, %xmm2
PCMPEQ %xmm0, %xmm3
pmovmskb %xmm2, %ecx
pmovmskb %xmm3, %eax
addl %eax, %ecx
jz L(first_vec_x0_test)
/* NB: We could move this shift to before the branch and save a
bit of code size / performance on the fall through. The
branch leads to the null case which generally seems hotter
than char in first 3x VEC. */
sall $16, %eax
orl %ecx, %eax
bsrl %eax, %eax
addq %rsi, %rax
#ifdef USE_AS_WCSRCHR
andq $-CHAR_SIZE, %rax
#endif
ret
.p2align 4
L(new_match):
pxor %xmm6, %xmm6
PCMPEQ %xmm9, %xmm6
pmovmskb %xmm6, %eax
sall $16, %ecx
orl %eax, %ecx
/* We can't reuse either of the old comparisons as since we mask
of zeros after first zero (instead of using the full
comparison) we can't gurantee no interference between match
after end of string and valid match. */
pmovmskb %xmm4, %eax
pmovmskb %xmm7, %edx
sall $16, %edx
orl %edx, %eax
leal -1(%ecx), %edx
xorl %edx, %ecx
andl %ecx, %eax
jz L(first_loop_old_match)
bsrl %eax, %eax
addq %rdi, %rax
#ifdef USE_AS_WCSRCHR
andq $-CHAR_SIZE, %rax
#endif
ret
END (strrchr)
weak_alias (strrchr, rindex)
libc_hidden_builtin_def (strrchr)
/* Save minimum state for getting most recent match. We can
throw out all previous work. */
.p2align 4
L(second_loop_match):
movq %rdi, %rsi
movaps %xmm4, %xmm2
movaps %xmm7, %xmm3
.p2align 4
L(second_loop):
movaps (VEC_SIZE * 2)(%rdi), %xmm4
movaps (VEC_SIZE * 3)(%rdi), %xmm5
/* Since SSE2 no pminud so wcsrchr needs seperate logic for
detecting zero. Note if this is found to be a bottleneck it
may be worth adding an SSE4.1 wcsrchr implementation. */
#ifdef USE_AS_WCSRCHR
movaps %xmm5, %xmm6
pxor %xmm8, %xmm8
PCMPEQ %xmm8, %xmm5
PCMPEQ %xmm4, %xmm8
por %xmm5, %xmm8
#else
movaps %xmm5, %xmm6
PMINU %xmm4, %xmm5
#endif
movaps %xmm4, %xmm9
PCMPEQ %xmm0, %xmm4
PCMPEQ %xmm0, %xmm6
movaps %xmm6, %xmm7
por %xmm4, %xmm6
#ifndef USE_AS_WCSRCHR
pxor %xmm8, %xmm8
PCMPEQ %xmm5, %xmm8
#endif
pmovmskb %xmm8, %ecx
pmovmskb %xmm6, %eax
addq $(VEC_SIZE * 2), %rdi
/* Either null term or new occurence of CHAR. */
addl %ecx, %eax
jz L(second_loop)
/* No null term so much be new occurence of CHAR. */
testl %ecx, %ecx
jz L(second_loop_match)
subl %ecx, %eax
jnz L(second_loop_new_match)
L(second_loop_old_match):
pmovmskb %xmm2, %ecx
pmovmskb %xmm3, %eax
sall $16, %eax
orl %ecx, %eax
bsrl %eax, %eax
addq %rsi, %rax
#ifdef USE_AS_WCSRCHR
andq $-CHAR_SIZE, %rax
#endif
ret
.p2align 4
L(second_loop_new_match):
pxor %xmm6, %xmm6
PCMPEQ %xmm9, %xmm6
pmovmskb %xmm6, %eax
sall $16, %ecx
orl %eax, %ecx
/* We can't reuse either of the old comparisons as since we mask
of zeros after first zero (instead of using the full
comparison) we can't gurantee no interference between match
after end of string and valid match. */
pmovmskb %xmm4, %eax
pmovmskb %xmm7, %edx
sall $16, %edx
orl %edx, %eax
leal -1(%ecx), %edx
xorl %edx, %ecx
andl %ecx, %eax
jz L(second_loop_old_match)
bsrl %eax, %eax
addq %rdi, %rax
#ifdef USE_AS_WCSRCHR
andq $-CHAR_SIZE, %rax
#endif
ret
.p2align 4,, 4
L(cross_page):
movq %rdi, %rsi
andq $-VEC_SIZE, %rsi
movaps (%rsi), %xmm1
pxor %xmm2, %xmm2
PCMPEQ %xmm1, %xmm2
pmovmskb %xmm2, %edx
movl %edi, %ecx
andl $(VEC_SIZE - 1), %ecx
sarl %cl, %edx
jz L(cross_page_continue)
PCMPEQ %xmm0, %xmm1
pmovmskb %xmm1, %eax
sarl %cl, %eax
leal -1(%rdx), %ecx
xorl %edx, %ecx
andl %ecx, %eax
jz L(ret1)
bsrl %eax, %eax
addq %rdi, %rax
#ifdef USE_AS_WCSRCHR
andq $-CHAR_SIZE, %rax
#endif
L(ret1):
ret
END(STRRCHR)
#ifndef USE_AS_WCSRCHR
weak_alias (STRRCHR, rindex)
libc_hidden_builtin_def (STRRCHR)
#endif

268
sysdeps/x86_64/wcsrchr.S
View File

@ -1,4 +1,4 @@
/* wcsrchr with SSSE3
/* wcsrchr optimized with SSE2.
Copyright (C) 2011-2022 Free Software Foundation, Inc.
This file is part of the GNU C Library.
@ -16,266 +16,12 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <sysdep.h>
.text
ENTRY (wcsrchr)
#define USE_AS_WCSRCHR 1
#define NO_PMINU 1
movd %rsi, %xmm1
mov %rdi, %rcx
punpckldq %xmm1, %xmm1
pxor %xmm2, %xmm2
punpckldq %xmm1, %xmm1
and $63, %rcx
cmp $48, %rcx
ja L(crosscache)
#ifndef STRRCHR
# define STRRCHR wcsrchr
#endif
movdqu (%rdi), %xmm0
pcmpeqd %xmm0, %xmm2
pcmpeqd %xmm1, %xmm0
pmovmskb %xmm2, %rcx
pmovmskb %xmm0, %rax
add $16, %rdi
test %rax, %rax
jnz L(unaligned_match1)
test %rcx, %rcx
jnz L(return_null)
and $-16, %rdi
xor %r8, %r8
jmp L(loop)
.p2align 4
L(unaligned_match1):
test %rcx, %rcx
jnz L(prolog_find_zero_1)
mov %rax, %r8
mov %rdi, %rsi
and $-16, %rdi
jmp L(loop)
.p2align 4
L(crosscache):
and $15, %rcx
and $-16, %rdi
pxor %xmm3, %xmm3
movdqa (%rdi), %xmm0
pcmpeqd %xmm0, %xmm3
pcmpeqd %xmm1, %xmm0
pmovmskb %xmm3, %rdx
pmovmskb %xmm0, %rax
shr %cl, %rdx
shr %cl, %rax
add $16, %rdi
test %rax, %rax
jnz L(unaligned_match)
test %rdx, %rdx
jnz L(return_null)
xor %r8, %r8
jmp L(loop)
.p2align 4
L(unaligned_match):
test %rdx, %rdx
jnz L(prolog_find_zero)
mov %rax, %r8
lea (%rdi, %rcx), %rsi
/* Loop start on aligned string. */
.p2align 4
L(loop):
movdqa (%rdi), %xmm0
pcmpeqd %xmm0, %xmm2
add $16, %rdi
pcmpeqd %xmm1, %xmm0
pmovmskb %xmm2, %rcx
pmovmskb %xmm0, %rax
or %rax, %rcx
jnz L(matches)
movdqa (%rdi), %xmm3
pcmpeqd %xmm3, %xmm2
add $16, %rdi
pcmpeqd %xmm1, %xmm3
pmovmskb %xmm2, %rcx
pmovmskb %xmm3, %rax
or %rax, %rcx
jnz L(matches)
movdqa (%rdi), %xmm4
pcmpeqd %xmm4, %xmm2
add $16, %rdi
pcmpeqd %xmm1, %xmm4
pmovmskb %xmm2, %rcx
pmovmskb %xmm4, %rax
or %rax, %rcx
jnz L(matches)
movdqa (%rdi), %xmm5
pcmpeqd %xmm5, %xmm2
add $16, %rdi
pcmpeqd %xmm1, %xmm5
pmovmskb %xmm2, %rcx
pmovmskb %xmm5, %rax
or %rax, %rcx
jz L(loop)
.p2align 4
L(matches):
test %rax, %rax
jnz L(match)
L(return_value):
test %r8, %r8
jz L(return_null)
mov %r8, %rax
mov %rsi, %rdi
test $15 << 4, %ah
jnz L(match_fourth_wchar)
test %ah, %ah
jnz L(match_third_wchar)
test $15 << 4, %al
jnz L(match_second_wchar)
lea -16(%rdi), %rax
ret
.p2align 4
L(match):
pmovmskb %xmm2, %rcx
test %rcx, %rcx
jnz L(find_zero)
mov %rax, %r8
mov %rdi, %rsi
jmp L(loop)
.p2align 4
L(find_zero):
test $15, %cl
jnz L(find_zero_in_first_wchar)
test %cl, %cl
jnz L(find_zero_in_second_wchar)
test $15, %ch
jnz L(find_zero_in_third_wchar)
and $1 << 13 - 1, %rax
jz L(return_value)
test $15 << 4, %ah
jnz L(match_fourth_wchar)
test %ah, %ah
jnz L(match_third_wchar)
test $15 << 4, %al
jnz L(match_second_wchar)
lea -16(%rdi), %rax
ret
.p2align 4
L(find_zero_in_first_wchar):
test $1, %rax
jz L(return_value)
lea -16(%rdi), %rax
ret
.p2align 4
L(find_zero_in_second_wchar):
and $1 << 5 - 1, %rax
jz L(return_value)
test $15 << 4, %al
jnz L(match_second_wchar)
lea -16(%rdi), %rax
ret
.p2align 4
L(find_zero_in_third_wchar):
and $1 << 9 - 1, %rax
jz L(return_value)
test %ah, %ah
jnz L(match_third_wchar)
test $15 << 4, %al
jnz L(match_second_wchar)
lea -16(%rdi), %rax
ret
.p2align 4
L(prolog_find_zero):
add %rcx, %rdi
mov %rdx, %rcx
L(prolog_find_zero_1):
test $15, %cl
jnz L(prolog_find_zero_in_first_wchar)
test %cl, %cl
jnz L(prolog_find_zero_in_second_wchar)
test $15, %ch
jnz L(prolog_find_zero_in_third_wchar)
and $1 << 13 - 1, %rax
jz L(return_null)
test $15 << 4, %ah
jnz L(match_fourth_wchar)
test %ah, %ah
jnz L(match_third_wchar)
test $15 << 4, %al
jnz L(match_second_wchar)
lea -16(%rdi), %rax
ret
.p2align 4
L(prolog_find_zero_in_first_wchar):
test $1, %rax
jz L(return_null)
lea -16(%rdi), %rax
ret
.p2align 4
L(prolog_find_zero_in_second_wchar):
and $1 << 5 - 1, %rax
jz L(return_null)
test $15 << 4, %al
jnz L(match_second_wchar)
lea -16(%rdi), %rax
ret
.p2align 4
L(prolog_find_zero_in_third_wchar):
and $1 << 9 - 1, %rax
jz L(return_null)
test %ah, %ah
jnz L(match_third_wchar)
test $15 << 4, %al
jnz L(match_second_wchar)
lea -16(%rdi), %rax
ret
.p2align 4
L(match_second_wchar):
lea -12(%rdi), %rax
ret
.p2align 4
L(match_third_wchar):
lea -8(%rdi), %rax
ret
.p2align 4
L(match_fourth_wchar):
lea -4(%rdi), %rax
ret
.p2align 4
L(return_null):
xor %rax, %rax
ret
END (wcsrchr)
#include "../strrchr.S"